I love this store.
But I would like to ask if I can create NPCs that sell the same articles? I can't find the right command.

? I don't understand what you mean when you say articles.

The point would be that each NPC knows how to sell all items, for example, the same set is sold by three NPCs.

Merged post

If you have HumanNPC set the shop list you want to true ID
"npc": true,
"npcID": 400753551,xxxxxxxxxx,xxxxxxxx,cxxxxxxx
                1NPC           2NPC       3NPC     4NPC

unfortunately I can't solve it here

? You will have to set up the same shop again and set a new NPC id to it. 

So currently each shop can have 1 NPC set to it. It does not support multiple NPCs to the same shop. 

This is because there is no relationship between one NPC and another so I have no way of knowing if they are in the same group. 

I'd have to create a group so that the NPCs could go into the same group. 

And add all the NPCs that should belong to each shop into the group and then say which ones are associated with said shop or shops and fetch those when the player goes to open that NPC shop. 

So this has become a feature request for now, and I hope this solves your questions. 

This feature request has been added/completed in the latest update 2.2.48